1. Field of the Invention
The present invention relates generally to occupancy sensor systems and methods, and, more particularly, to an energy saving system and method for forcing only one of a series of banks of lighting to automatically activate upon initial detection of the occupancy of an area.
2. Description of the Related Art
An occupancy sensor system controls activation or deactivation of a system connected thereto responsive to sensing occupancy of an area covered thereby. The sensors in an occupancy sensor system may include infrared and/or ultrasonic technologies. The systems controlled thereby may consist of lighting systems, heating and air conditioning systems, alarm systems, and/or building automation systems. The area covered by an occupancy sensor may constitute a room, a class-room, a computer room, a section of a floor, and/or a floor in a building, anywhere from very small to very large areas. The occupancy sensor may be mounted at a location in the wall or in the ceiling of the area to be covered thereby.
Occupancy sensors conserve energy by activating and deactivating systems automatically depending upon occupancy of areas. Such energy conservation has been important for environmental and economic reasons, and has been mandated where such conservation is essential. In view of such considerations, increasingly offices and other areas utilize multiple groups or banks of lights. Grouping the lighting into separate banks allows occupants to select only a portion of the room lighting, thereby saving energy. Such selection is commonly used when performing computer based tasks, to reduce glare on the monitor. In several states, it is required that all offices use two sets of lights to implement energy savings and thereby reduce energy demand.
In individual offices, for instance, there may be two banks of light. Often the banks of lights are set up such that half of each fixture is part of each bank. However, it is often not readily apparent that both sets of lights are on. Further, other occupants, such as cleaning crews, may change the remembered setting from the primary occupant. Where the remembered setting is for all banks of lights to turn on upon entry into the area, energy is wasted.
Therefore, there has existed a need for a system which is capable of forcing automatic activation of only one of the banks of lights, regardless of the last light-activating setting selected by the user, to enforce a maximum amount of energy savings. The present invention fulfills these needs.